CNS/PNS Intro, CNS Embrology Flashcards
3 Planes to section the brain and spinal cord
1) coronal plane
2) sagittal plane
3) axial plane
Locations of Neuro Lesions
-Left/Right
-Rostral/Caudal
Forebrain, Hindbrain, Brainstem, Spinal Cord, Nerve Root, Peripheral Nerve, Nerve Muscle Junction, Muscle
Telencephalon
-includes cerebral hemishperes
Diencephalon
-hypothalamus & thalamus
Mesencephalon
-midbrain
Metencephalon
-pons & cerebellum
Rhombencephalon
-medulla
“Gray Matter”
- CNS regions with high packing densities of neurons
- appear darker
- much is on the surface of the brain
- located deep/center of the spinal cord
“White Matter”
- regions with higher densities of axons (high fat content and myelin covering that acts as insulation)
- appear lighter
- all lies deep in the brain
- located on surface of spinal cord
5 Major Subdivisions of the Forebrain
1) frontal
2) parietal
3) temporal
4) limbic
5) occipital
Basal Ganglia
-involved in smoothing out motor movements of the limbs & axial musculature during body movement
Thalamus
- involved as a relay center for all external sensory information being passed along to the forebrain
- important regulatory center along with the hypothalamus for the autonomic nervous system
Main Components of the Brainstem
- midbrain
- pons
- medulla (connects brain to spinal cord)
How many cervical spinal cord segments are there?
8, only 7 vertebrae
How many thoracic spinal cord segments?
12, 12 vertebrae
How many lumbar spinal cord segments?
5, 5 vertebrae
How many sacral spinal cord segments?
5 - fused with sacral vertebra making sacral bone
What happens with spinal cord as child grows?
-its pulled rostrally so the lower thoracic, lumbar, and sacral nerves exit the spinal canal several segments below their exit from the spinal cord
Where does the spinal cord end?
-T12-L1 vertebrae
Grey matter organization in spinal cord?
–bilateral dorsal horns and bilateral ventral horns
Dorsal Root of Spinal Cord
-serves afferent (peripheral sensory nerve fibers traveling to the cord)